I gotta LTD, it seems to me like you are setting yourself up for serious disappointment.
You’ve approached this relationship with an expectation that you will acquire her from it - eventually she will catch on to that and suddenly she will start to suspect your help. Second guess her decision because you helped her make it.
The best case scenario if that happens is that you end up becoming friends who don’t really hang out except for specific reasons (like sitting together at Church).
The worst is her going back to her ex AND harbouring negative feelings towards you.
This is the essential problem with having a girl that you allow yourself to be attracted to as a friend… even if your advice is correct, once you’ve given it you can’t really move in on her for a LONG TIME after it’s been given.
IMO you really only have two options:
Straight up tell her that you like her, you liked her for a long time now, you still think her ex was bad for her, but you want to be with her.
In other words, be brutally honest about your expectations. At this point if nothing happens between you two you will end up feeling bad around her and the friendship will not be a positive one for your personal development anyways.
The other option is much more difficult - give up those expectations of it going anywhere with her. Hang out with her not expecting ANYTHING to EVER happen, just simply being with her because you genuinely enjoy her company.
The danger here is lieing to yourself, harbouring a secret wish that maybe something will happen. Believe me when I say that is dangerous to your own mental health… and will undoubtedly end up in heartbreak.
This is one of the biggest problem guys have, they try to sit on a fence with girls. Pretend to be their friend while they secretely wish that they could be more. A relationship built on expectations is NOT REAL. Real relationships are defined by actions not expectations.
So yes, this means either man up and be honest with what you want, or choose to not want it.
BTW - If you do choose Path #2 and later decide that you really can’t do it DO NOT PROCRASTINATE IN TELLING HER.
Think about your relationships with men… do you ever make friends with a guy because you hope that you will get something from him for the friendship (other than the benefits of being friends). I don’t and the only example I can think of where men make friends with men for that purpose is brown-nosers at work.
We all know how well those relationships typically work out for brown-nosers (TV actually gets this pretty right) - Yes the brown-noser maybe gets what he wants… but at what cost to his integrity?
Be decisive and polarize your relationship. Humpty Dumpty is the world’s most famous fence sitter and we all know how well that worked out for him.